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Hi All
Maybe you have already seen this but it is new to me.
Slo.it is launching a new IL crown with an interesting assembly.
You can read more on the LeTrat Slot blog: https://www.letratsl...tit-couronnes-m
It looks quite interesting.
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Another view of the new crown assembly here:

http://www.slotcar-today.com/en/notices ... t-7236.php

Can't say I'm in to this... too many fiddly fuggly parts for these old fingers.

Prefer the K.I.S.S. doctrine.....

What problem is this gear solving? Like a lot of guys here, I have dabbled in 1:1 scale cars, in my case mostly Lotus, over the years. On Lotus forums there are guys who, upon getting a car, immediately post up asking about what kinds of go fast mods one should do. Invariably the answer is that spending a couple thousand at a driving school will yield better performance than any modification, especially for less experienced drivers.

In slot cars, I think whatever advantage might be had with a crown gear like this will be realized only by guys who've already tweaked/tuned their cars to within an inch of their lives, and are also extremely competent drivers.

While it may reduce the wear/friction as described in the announcement, I must agree with Jesla. The good old standard crown gear has worked just fine for me over the years.

I have some Sportsman models with who knows how many laps in combat. None of them have any wear to speak of. Properly lubricated, as with most any gear, they work just fine.

Clearly the competitive endurance racer could benefit though. Time will tell as usual.

Personnally, I think it's over engineered.
Parma's been doing it right for years. Use spacers between the bushings and the wheels (instead of the motor shaft) to set the side to side play, and put the gear where you want it. Scaleauto and I think NSR gears allow this as well. No worries about the motor shaft wearing down the surface area.

To me it looks like with this system it is much easier to set the right mesh between the pinion and the gear.
No need to fiddle with spacers especially when there is not much space available.
As already said, this could bring some advantages in the endurance races.
I am thinking here at the DiSCA 24h: changing tyres in the LMP2 will be quicker with this approach.

I also agree with many of the previous comments. What gets my nighty in a twist is where it says that the crown wheel groove keeps the motor shaft where it needs to be. Whaaaaaaaaaaaaaaaaaaaaat????????????


However Slotit people are clever people so there is probably something I don't see here.

Considering that the majority of folks in the hobby likely use the motor shaft in conjunction with a "slotted" crown to provide gear mesh, this system does offer some benefits, While the benefits are there, they are not massive by any means, and and a switch to this type of new gear will not make you a world beater.

This new Crown will offer some friction advantages due to the 2 "thrust" washers being incorporated, particularly in left hand corners, where the axle shifts due to lateral loads, and the motor shaft contacts the face of the crown centering slot. While this does happen on both left and right hand corners, it is particularly a problem on left hand corners, as in this situation, the motor shaft is spinning in the opposite direction to the Crown....obviously not ideal for a variety of reasons ;)

So, from an engineering point of view, this new design does make sense, and while the benefits are there, they are small.

If you routinely inspect/lubricate your motor shaft/Crown slot, the differences will be very small, but, the differences are there, so, if you are looking to save every 1000th of a sec. possible, the new design makes sense.

That said, if you are really looking to save every 1000th possible, using the motor shaft as part of the gear meshing process is far from ideal.

The following are three levels of inline gear set up....depending on your abilities/patience/tools ,and, willingness to cut motor shafts.

1/ GOOD........Leave the motor shaft as is.....place spacers between the wheels and axle bushings to eliminate lateral axle play, and set the Crown so the slot faces just clear the motor shaft on either side.

2/ BETTER........Trim the motor shaft flush with the end of the pinion........spacers between the wheels/axle bushings, set the Crown with just a hint of lash.

3/ BEST.........Trim the motor shaft.......place spacers between the OUTER edges of the Crown and the INSIDE axle bushing faces.....you will need a bit of patience, and a good variety of spacer widths (several .005"), and add/subtract spacers so the a small amount of lash is present (in both directions)......tighten your Crown, and you are good to go !!
This method eliminates any chance of the mesh going "off" should your wheels happen to move laterally on your car........this happens more than you think, just check the lateral axle play on one of your cars after a race.
For anyone racing enduros etc. this method also allows wheels/tires to be changed quickly without affecting the mesh one bit.
Most high end inline (BSCRA, Eurosport etc. etc ) are run this way, and have run this way for years.

Cheers
Chris Walker

What Chris said.
I adopted his method of spacers within the pinion and crown cage.
And yes it is the best setup i can recall for gear mesh and bullet proof performance.
Slot it has a good idea if you don't like Chris's best method or find it frustrating, but it is bullet proof for gear mesh.
Good one Chris
Bob